Objects appear normal in material preview but in rendered mode with cycles they're encased in weird material blobs
The 'blob' happens when you set high Midlevel in the Displacement node.
Yours is set to 4,2 (default is 0,5)


The 'blob' cannot be selected, because it's just displaced polygons
It only happens in Cycles preview, because Eevee preview doesn't support displacement
Noise texture only suplies values 0-1, so high midlevel may look weird



  Displacement Midlevel
  Neutral displacement value that causes no displacement. With the default 0.5, any lower values will cause the surfaces to be
  pushed inwards, and any higher values will push it outwards.
  
  Blender Manual